1. Field of the Invention
The present invention relates to a device for analyzing a polyphase mixture via a light beam backscattered by said mixture. The device may include:                a cell having a capacity component of vertical extent, capable of containing the polyphase mixture,        means for emitting a light beam in the direction of the cell, so that the light beam extends in a vertical plane covering at least a height of the cell capable of containing the polyphase mixture,        means for receiving the light beam backscattered by said polyphase mixture, covering a backscattered light beam height extending over the height of the cell capable of containing the polyphase mixture.        
2. Description of Related Art
Such a device is known for example from the document US 2002/0147563. The measurement of the backscattered light beam with the device according to this document is not satisfactory. This is because any distance of the cell from the backscattering receiver means leads to a great loss of spatial resolution of the measurement.
The document EP 1 241 467 is furthermore known, which relates to an apparatus for inspection and to a system for inspection of foreign matter in containers filled with a liquid. The monitoring device described in this document comprises in particular a light source which sends irradiation light to the transparent container, a means for taking images of the irregular reflection light reflected by the foreign matter contained in the liquid, and an image processing means detecting foreign matter in the liquid.
The document WO 2008/092537 is furthermore known, which relates to an optical characterization device in which a sample is arranged in a light-transparent receptacle, a camera being provided in order to detect the sample. A first light source is arranged so that the sample is lit through in a direction counter to the line of view of the camera. A second light source is arranged on the same side as the camera, and a laser source is arranged transversely to the line of view of the camera.
The document FR 2 841 983 in the name of the Applicant is also known, which relates to a method and a device for measuring a light flux backscattered by a disperse medium, not perturbed by the reflections at the interfaces; the device makes it possible to measure a light flux backscattered by a disperse medium placed on a first side of the wall, by interaction with a plurality of light rays emitted on the second side of the wall, opposite the first side where the disperse medium is placed, and in the direction of said medium, the plurality of light rays being capable of passing through the wall and being at least partially backscattered by the disperse medium in the direction of reception means placed on the second side of the wall, said wall being capable of being passed through by the emitted and backscattered light rays, and of being in contact with the disperse medium. The device comprises:                means for emitting, toward the wall, light radiation capable of passing through this wall and reaching the disperse medium, so that the latter can in turn emit a plurality of backscattered light rays through the wall with a view to forming a backscattering spot in which at least one central disk-shaped region is defined, the center of which corresponds to the light centroid of the backscattering spot and the radius of which is equal to four times the maximum free transport path l*max of the disperse medium, the backscattering spot being capable of being imaged at least in part on the reception means,        means for receiving the light radiation backscattered by the disperse medium through the wall and intended to form the backscattering spot, these reception means covering at least a direction extending from the light centroid of said spot,        means for suppressing, from the light rays backscattered by the disperse medium, the light rays which come from the central region and have experienced total reflection on the surface forming the interface of the wall with the second side,        means for measuring spatial sampling of the profile of the light flux received by at least a part of the reception means.        